The invention relates to novel human kinase-like nucleic acid sequences and proteins. Also provided are vectors, host cells, and recombinant methods for making and using the novel molecules.
Phosphate tightly associated with a molecule, e.g., a protein, has been known since the late nineteenth century. Since then, a variety of covalent linkages of phosphate to proteins have been found. The most common involve esterification of phosphate to serine, threonine, and tyrosine with smaller amounts being linked to lysine, arginine, histidine, aspartic acid, glutamic acid, and cysteine. The occurrence of phosphorylated molecules, e.g., proteins, implies the existence of one or more kinases, e.g., protein kinases, capable of phosphorylating various molecules, e.g., amino acid residues on proteins, and also of phosphatases, e.g., protein phosphatases, capable of hydrolyzing various phosphorylated molecules, e.g., phosphorylated amino acid residues on proteins.
Protein kinases play critical roles in the regulation of biochemical and morphological changes associated with cellular growth and division (D""Urso et al. (1990) Science 250:786-791; Birchmeier et al. (1993) Bioessays 15:185-189). They serve as growth factor receptors and signal transducers and have been implicated in cellular transformation and malignancy (Hunter et al.(1992) Cell 70:375-387; Posada et al. (1992) Mol. Biol. Cell 3:583-592; Hunter et al. (1994) Cell 79:573-582). For example, protein kinases have been shown to participate in the transmission of signals from growth-factor receptors (Sturgill et al.(1988) Nature 344:715-718; Gomez et al. (1991) Nature 353:170-173), control of entry of cells into mitosis (Nurse (1990) Nature 344:503-508; Maller (1991) Curr. Opin. Cell Biol. 3:269-275) and regulation of actin bundling (Husain-Chishti et al. (1988) Nature 334:718-721).
Protein kinases can be divided into different groups based on either amino acid sequence similarity or specificity for either serine/threonine or tyrosine residues. A small number of dual-specificity kinases have also been described. Within the broad classification, kinases can be further subdivided into families whose members share a higher degree of catalytic domain amino acid sequence identity and also have similar biochemical properties. Most protein kinase family members also share structural features outside the kinase domain that reflect their particular cellular roles. These include regulatory domains that control kinase activity or interaction with other proteins (Hanks et al. (1988) Science 241:42-52).
The entry and progression of cells through the cell cycle are controlled by changes in the levels and activities of cyclins. The levels of several of the cyclins (A, B, and E) peak during specific phases of the cell cycle, then are rapidly degraded as the cell enters the next phase of the cell cycle. Cyclins perform their function by forming complexes with a group of constitutively expressed proteins called cyclin-depended kinases (CDKs). Different combinations of cyclins and CDKs are associated with each of the important transitions in the cell cycle.
Cyclin B is synthesized and binds to CDK1 during the transition of the cell into the G2 phase of the cell cycle. This forms the B/CDK1 complex which is necessary for the cells to enter the M phase. The complex is activated by phos-phorylation,and the active kinase then phosphorylates a variety of proteins involved in mitosis, DNA replication, depolymerization of the nuclear lamina, and mitotic spindle formation.
Kinases play a role in the transduction of signals for cell proliferation, differentiation, and apoptosis. Alteration in such genes and their products are frequent in human cancers. Deregulated cell proliferation is the hallmark of cancer. Alteration in such genes and their products are frequent in human cancer. Modulation of these genes and their regulatory activities may permit the control of tumor cell proliferation and invasion.
Kinases play critical roles in cellular growth. Therefore, novel kinase polynucleotides and proteins are useful for modulating cellular growth, differentiation and/or development.
Isolated nucleic acid molecules corresponding to kinase-like nucleic acid sequences are provided. Additionally, amino acid sequences corresponding to the polynucleotides are encompassed. In particular, the present invention provides for isolated nucleic acid molecules comprising nucleotide sequences encoding the amino acid sequence shown in SEQ ID NO:2 or the nucleotide sequences encoding the DNA sequence deposited in a bacterial host as ATCC Accession Number PTA-2342. Further provided are kinase-like polypeptides having an amino acid sequence encoded by a nucleic acid molecule described herein.
The present invention also provides vectors and host cells for recombinant expression of the nucleic acid molecules described herein, as well as methods of making such vectors and host cells and for using them for production of the polypeptides or peptides of the invention by recombinant techniques.
The kinase-like molecules of the present invention are useful for modulating cell growth, cell transformation, cellular signal transduction, and apoptosis. The molecules are useful for the diagnosis and treatment of any disorder wherein there is aberrant cell growth and/or division or aberrant signal transduction. Alterations in such molecules are frequent in human cancer. A cell cycle-regulated kinase designated clone 12832 is disclosed. Modulation of 12832 and kinase-like molecules of the invention may permit control of tumor cell proliferation and invasion. More specifically, these molecules are useful for the diagnosis and treatment of cellular growth, cellular cycling, and cellular differentiation involving the following human tissues: heart, lung, skin, testis, colon, thymus, tonsil, lymph node, placenta, fetal heart, fetal liver, fetal spinal cord, and undifferentiated and differentiated osteoblasts. Accordingly, in one aspect, this invention provides isolated nucleic acid molecules encoding kinase-like proteins or biologically active portions thereof, as well as nucleic acid fragments suitable as primers or hybridization probes for the detection of kinase-like-encoding nucleic acids.
Another aspect of this invention features isolated or recombinant kinase-like proteins and polypeptides. Preferred kinase-like proteins and polypeptides possess at least one biological activity possessed by naturally occurring kinase-like proteins.
Variant nucleic acid molecules and polypeptides substantially homologous to the nucleotide and amino acid sequences set forth in the sequence listings are encompassed by the present invention. Additionally, fragments and substantially homologous fragments of the nucleotide and amino acid sequences are provided.
Antibodies and antibody fragments that selectively bind the kinase-like polypeptides and fragments are provided. Such antibodies are useful in detecting the kinase-like polypeptides. In another aspect, the present invention provides a method for detecting the presence of kinase-like activity or expression in a biological sample by contacting the biological sample with an agent capable of detecting an indicator of kinase-like activity such that the presence of kinase-like activity is detected in the biological sample.
In yet another aspect, the invention provides a method for modulating kinase-like activity comprising contacting a cell with an agent that modulates (inhibits or stimulates) kinase-like activity or expression such that kinase-like activity or expression in the cell is modulated. In one embodiment, the agent is an antibody that specifically binds to kinase-like protein. In another embodiment, the agent modulates expression of kinase-like protein by modulating transcription of a kinase-like gene, splicing of a kinase-like mRNA, or translation of a kinase-like mRNA. In yet another embodiment, the agent is a nucleic acid molecule having a nucleotide sequence that is antisense to the coding strand of the kinase-like mRNA or the kinase-like gene.
In one embodiment, the methods of the present invention are used to treat a subject having a disorder characterized by aberrant kinase-like protein activity or nucleic acid expression by administering an agent that is a kinase-like modulator to the subject. In one embodiment, the kinase-like modulator is a kinase-like protein. In another embodiment, the kinase-like modulator is a kinase-like nucleic acid molecule. In other embodiments, the kinase-like modulator is a peptide, peptidomimetic, or other small molecule.
The present invention also provides a diagnostic assay for identifying the presence or absence of a genetic lesion or mutation characterized by at least one of the following: (1) aberrant modification or mutation of a gene encoding a kinase-like protein; (2) misregulation of a gene encoding a kinase-like protein; and (3) aberrant post-translational modification of a kinase-like protein, wherein a wild-type form of the gene encodes a protein with a kinase-like activity.
In another aspect, the invention provides a method for identifying a compound that binds to or modulates the activity of a kinase-like protein. In general, such methods entail measuring a biological activity of a kinase-like protein in the presence and absence of a test compound and identifying those compounds that alter the activity of the kinase-like protein.
The invention also features methods for identifying a compound that modulates the expression of kinase-like genes by measuring the expression of the kinase-like sequences in the presence and absence of the compound.
Other features and advantages of the invention will be apparent from the following detailed description and claims.